In this case, the big word in the deadly force triangle is capability. The VA has already established opportunity and intent; Most of the time, intent is the most complex and subjective point of a deadly force encounter. In this case, there are many variables that come into play. You have to take into account the VCs size, aproximated strength; is the perp armed? What is his demeanor? Do you know the perp and are you aware of his physical capabilities? Basicly, do you stand a reasonable chance in a hand to hand encounter? It reminds me of my one (civilian, off duty) encounter. An unarmed 17 year old attempted to mug me outside a 7-11. I verbaly resisted him, when he bagan to close into my reactionary gap I drew my Springfield. He emidiatly turned and ran. Called to mind, if he had continued to advance(he was at about 9 feet when I drew and backpedled a few steps), I probably would have lowered my weapon and to the ready and went with passive hand to hand(alot of sidestepping, jabs and thrusts to the throat if he had tried to disarm me).
Keep in mind; I am about 6'1", 220lbs, in pretty good shape; the VC was 5'10", 172lbs. I have a good amount of combat training and the size advantage. In my mind, if he had a weapon, he would have made a move for it and I would have acted acordingly. I could have defended myself without use of a weapon in that situation, if I had shot an unarmed 17 year old child, you could imagine that I would be in prision for a long, long time, especially since a good amount of it was caught on survailence tape. Now, If the VC was, say, 6'9" 300lbs, I would have again acted acordingly by double tapping the chest cavity, for which I would have been completely justified.
For the record, after the incident I called 9-11; after my description and the survailance footage, he was arretsted two days later at a near by WaWa gas station.